1. Field of the Invention
The present invention relates to a disk cartridge protecting a recording surface of an accommodated disk that is an information recording/reproduction medium, from contaminants, such as dust or a fingerprint, and particularly, to a disk player using a disk cartridge having a case having an opening, a shutter opening/shutting the opening of the case, a cover covering the case, and a disk disposed between the shutter and the cover.
2. Description of the Related Art
In general, a disk cartridge accommodates a disk that is an information recording/reproduction medium and is installed in a disk drive. As shown in FIG. 1, a conventional disk cartridge 100 includes a case 101 accommodating a disk D, a shutter 110 installed in the case 101 to be capable of rotating to selectively open and shut an opening 102 formed on the case 101 so that a pickup (not shown) of a disk drive can access the disk D, and a cover 103 fixed to an upper portion of the case 101. The cover 103 includes a hole 103b formed in the cover 103 for disk exchange and clamping, and an escape prevention lever 103a installed at the cover 103 to be capable of sliding along a side of the cover to prevent the disk D from escaping through the hole 103b. Thus, when the disk D is installed in the disk cartridge, the escape prevention lever 103a is pulled back not to interfere with the disk D. After the disk installation is completed, the escape prevention lever 103a is pushed forward so that an end portion of the escape prevention lever 103a prevents the disk D from escaping through the hole 103b. 
When the disk cartridge 100 accommodating the disk D is inserted into a disk drive as shown in FIG. 2A, an opening lever 120 installed at the disk drive pushes a locking piece 111a so that a protrusion 111c of the shutter 110 is unlocked from a groove 101a of the case 101. Then, the opening lever 120 pushes an interference piece 111b to have the shutter 110 pivot around left and right pivot axles 110a. The shutter 110 is formed of first and second shutter portions 111 and 112 respectively installed to be capable of pivoting around corresponding ones of the left and right pivot axles 110a and engaging each other through an engagement gear portion 113. As the first shutter portion 111 incorporated with the interference piece 111b rotates clockwise, the second shutter portion 112 rotates counterclockwise so that the first and second shutter portions 111 and 112 are separated apart from each other to open the opening 102. Then, a turntable (not shown) and a damper (not shown) of the disk drive enter the opening 102 and the hole 103a to clamp the disk D. A pickup (not shown) accesses a recording surface of the disk D to perform an information recording and/or reproducing process. Although not shown in the drawings, a torsion spring elastically biasing the first shutter portion 111 in a counterclockwise direction on the drawings, that is, in a direction to close the opening 102, is installed between the first shutter portion 111 and a bottom surface of the case 101. When a force applied by the opening lever 120 is removed, the shutter 110 is returned to an original closed position.
However, in the above structure, dust can intrude through the open hole 103b of the cover 103. Of course, since an upper surface of the disk D facing the hole 103b is not a surface for recording, direct contamination due to the dust does not occur. Nonetheless, when the dust is introduced and placed on the shutter 110, the dust disposed on the shutter 110 adheres to the recording surface of the disk D during an opening/shutting operation. Also, even if not necessarily caused by use of the shutter 110, there is a high possibility that the recording surface of the disk D is contaminated by the dust.
Furthermore, since the shutter 110 is installed in the case 101, and the disk D is placed on the shutter 110 during the opening/shutting operation of the shutter 110, the shutter 110 contacts the recording surface of the disk D (a lower surface of a disk in the drawings) so that the recording surface of the disk D may be scratched and damaged by the shutter 110.
Also, in the above structure, when the shutter 110 is pressed hard through the opening 102 in a state in which the shutter 110 is closed, the shutter 110 is easily deformed. That is, since each of the first and second shutter portions 111 and 112 is supported by the case 101 through one end thereof being coupled to be capable of pivoting around the pivot axle 110a, when a user presses the other end of the shutter 110 through the opening 102, the shutter 110 is easily deformed. As a result, the opening/shutting operation is not performed properly. Even if the opening/shutting operation is properly performed, a gap may be formed between the first and second shutter portions 111 and 112 which may be prevented from performing a function as a shutter.
Therefore, an improved structure is needed to prevent deformation of the shutter 110 and introduction of the dust while the recording surface of a disk is protected.